Running League of Legends At School

So I am hosting a League of Legends club at my school and the tech services for my school are trying to help us get it to work at school. Problem is, the tech services said it works, but they "Unfortunately the needed firewall ports are closed on our network and we do not want to open them for security purposes" and "We do not want any outside attacks or threats to occur by opening these ports". My idea was to open the ports for only a certain time (like two hours after school) but they said there isn't a function for that in there firewall. Any ideas of how we can fix this? Please help